Description of problem:
For auto.net, If one umount the mount point mounted by autofs(automount)
manually, automount don't mount it again and after the umount even a new
accesses come, accessings under that mount point fail.
Version-Release number of selected component (if applicable):
all version all release.
How reproducible:
100% reproducible.
Steps to Reproduce:
1. umount the mount point mounted by autofs(automount) mannually,
2. access under that just umounted mount point.
3.
Actual results:
accessings fail.
Expected results:
accessings succeed.
Additional info:
a patch aganst kernel-2.6.9-34.0.1 is made as attached. please get this included
in update 5.

Autofs version 4 mounts each multimount hierarchy as a single unit. What this
means is that autofs cannot determine that a leaf node in this hierarchy was
unmounted. As such, this problem can only be fixed for non-hierarchical mounts.
Fixing the problem for only that case will cause inconsistent behaviour, so I
do not believe the change is warranted.
Further, one should not unmount autofs managed mount points by hand. You can
send SIGUSR1 to the daemon to tell it to unmount currently mounted shares.
Version 5 of the automounter takes steps to address this problem, though
unmounting shares by hand is not recommended.

hi Ian and Jeffrey,
to Ian:
I think what you metioned should be solved by user space program specified in
master map, like auto.master, if there are problems.
to Jeffrey:
yes, the change takes no effect on multimount hierarchy, because the upper level
mounted FS receives the request and autofs won't be notified.
Sometimes users don't rules and they like their convenient way. It's better we
make autofs robuster.
will autofs version 5 be included in RHEL4.5?
wengang.